Parallel paths across the Pacific: a speculative explanation for the dilep in Marshallese navigation

TL;DR

This paper proposes a new mechanism explaining the dilep wave pattern used by Marshallese navigators, offering testable predictions to understand its causal basis and improve traditional navigation techniques.

Contribution

It introduces a speculative mechanism for the dilep phenomenon, linking wave patterns to island reflections and refractions, with testable predictions for future validation.

Findings

Proposes a causal mechanism for the dilep phenomenon.

Predicts wave pattern behaviors that can be tested with satellite and experimental data.

Provides a framework for ethnographic and hydrodynamic validation.

Abstract

Traditional techniques used by navigators in the Marshall Islands include the use of wave patterns as influenced by reflection and refraction around islands. The dilep is one such pattern, apparently providing signals to guide a navigator directly between two distant islands; so far there is no agreed causal explanation for such a phenomenon. We propose a mechanism; this generates a number of qualitative and quantitative predictions that may in principle be tested against satellite photo evidence, hydrodynamic simulations, experiments by small boat navigators in the right conditions, and ethnographic reports.